From 92aadb6a5eeec75edf7f5a11a0ebd861dd85ca6b Mon Sep 17 00:00:00 2001
From: N Balachandran <nbalacha@redhat.com>
Date: Mon, 20 May 2019 15:23:42 +0530
Subject: [PATCH 148/169] cluster/dht: Lookup all files when processing
 directory

A rebalance process currently only looks up files
that it is supposed to migrate. This could cause issues
when lookup-optimize is enabled as the dir layout can be
updated with the commit hash before all files are looked up.
This is expecially problematic if one of the rebalance processes
fails to complete as clients will try to access files whose
linkto files might not have been created.
Each process will now lookup every file in the directory it is
processing.
Pros: Less likely that files will be inaccessible.
Cons: More lookup requests sent to the bricks and a potential
performance hit.
Note: this does not handle races such as when a layout is updated on disk
just as the create fop is sent by the client.

upstream : https://review.gluster.org/#/c/glusterfs/+/22746/

>Change-Id: I22b55846effc08d3b827c3af9335229335f67fb8
>fixes: bz#1711764

BUG#1714124

Change-Id: Ica6a9459befe53957f080001a2dda525b3b14d1c
Signed-off-by: N Balachandran <nbalacha@redhat.com>
Reviewed-on: https://code.engineering.redhat.com/gerrit/172080
Tested-by: RHGS Build Bot <nigelb@redhat.com>
Reviewed-by: Mohit Agrawal <moagrawa@redhat.com>
---
 xlators/cluster/dht/src/dht-rebalance.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/xlators/cluster/dht/src/dht-rebalance.c b/xlators/cluster/dht/src/dht-rebalance.c
index efbe8a4..559f046 100644
--- a/xlators/cluster/dht/src/dht-rebalance.c
+++ b/xlators/cluster/dht/src/dht-rebalance.c
@@ -2741,12 +2741,6 @@ gf_defrag_migrate_single_file(void *opaque)
         goto out;
     }
 
-    if (!gf_defrag_should_i_migrate(this, rebal_entry->local_subvol_index,
-                                    entry->d_stat.ia_gfid)) {
-        gf_msg_debug(this->name, 0, "Don't migrate %s ", entry_loc.path);
-        goto out;
-    }
-
     gf_uuid_copy(entry_loc.gfid, entry->d_stat.ia_gfid);
 
     gf_uuid_copy(entry_loc.pargfid, loc->gfid);
@@ -2772,6 +2766,12 @@ gf_defrag_migrate_single_file(void *opaque)
         goto out;
     }
 
+    if (!gf_defrag_should_i_migrate(this, rebal_entry->local_subvol_index,
+                                    entry->d_stat.ia_gfid)) {
+        gf_msg_debug(this->name, 0, "Don't migrate %s ", entry_loc.path);
+        goto out;
+    }
+
     iatt_ptr = &iatt;
 
     hashed_subvol = dht_subvol_get_hashed(this, &entry_loc);
-- 
1.8.3.1